Effects of Different Damage Treatments on Photosynthetic Characteristics and Chlorophyll Fluorescence Parameters of Aquilaria sinensis (Lour.) Spreng.

【Objective】The experiment was to study the effects of different damage treatments on the photosynthetic characteristics and fluorescence parameters of the leaves of Aquilaria sinensis, improve the formation rate of A. sinensis, facilitate the quality of A. sinensis close to the natural quality, meet the needs of medicine and health, maintain the health of the people, realize the protection and sustainable utilization of wild A. sinensis resources.【Method】By using 15-yearold A. sinensis trees as tested material and no any damage treatment as control group, different wound treatments on the trees were implemented in July（A:No cutting; B:1/3 cutting of lateral branch and lateral root; C:2/3cutting of lateral branchand lateral root; D:stem cutting-off). The photosynthetic characteristics and chlorophyll fluorescence parameters of A. sinensis (Lour.) Spreng was measured after treatments.【Result】The results showed that: (1) compared with the control group, the photosynthetic parameters of leaves in the three groups treated with B, C and D were significantly different, which may be due to the enhanced photosynthetic capacity of mesophyll cells after injury. (2) the photosynthetic parameters of the leaves of agarwood in the cut-off treatment(group D) increased significantly, indicating that the leaves of agarwood in the cut-off treatment had the strongest photosynthetic capacity. (3) The maximum photochemical efficiency (Fv/Fm) and PS Ⅱ potential activity (Fv/F0) of treatment A, B and C had no difference with those of control group. 【Conclusion】Under treatment D, the photosynthetic characteristics and fluorescence parameters of A. sinensis were significantly different from those of the control group and, stem cutting-off treatment improved the photosynthesis of A. sinensis significantly. Treatment A, B and C had no great influence on the growth of the trees, while the relationship between the photosynthesis capacity and the accumulation of photosynthetic products and agarwood formation rate remains to be further discussed.